mirrors
/
SDWebImage
mirror of https://github.com/SDWebImage/SDWebImage.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Use the weak-strong dancing and the weak reference to manager instance to avoid the leak of runningOperations

This commit is contained in:
DreamPiggy 2018-01-15 15:31:59 +08:00
parent 0ad1ffa012
commit 9c7224fd50
1 changed files with 21 additions and 38 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

59
SDWebImage/SDWebImageManager.m
View File

@ -13,8 +13,9 @@
@interface SDWebImageCombinedOperation : NSObject <SDWebImageOperation> @interface SDWebImageCombinedOperation : NSObject <SDWebImageOperation>
@property (assign, nonatomic, getter = isCancelled) BOOL cancelled; @property (assign, nonatomic, getter = isCancelled) BOOL cancelled;
@property (copy, nonatomic, nullable) SDWebImageNoParamsBlock cancelBlock; @property (strong, nonatomic, nullable) SDWebImageDownloadToken *downloadToken;
@property (strong, nonatomic, nullable) NSOperation *cacheOperation; @property (strong, nonatomic, nullable) NSOperation *cacheOperation;
@property (weak, nonatomic, nullable) SDWebImageManager *manager;
@end @end
@ -125,6 +126,7 @@
} }
__block SDWebImageCombinedOperation *operation = [SDWebImageCombinedOperation new]; __block SDWebImageCombinedOperation *operation = [SDWebImageCombinedOperation new];
operation.manager = self;
__weak SDWebImageCombinedOperation *weakOperation = operation; __weak SDWebImageCombinedOperation *weakOperation = operation;
BOOL isFailedUrl = NO; BOOL isFailedUrl = NO;
@ -150,8 +152,9 @@
if (options & SDWebImageQueryDiskSync) cacheOptions |= SDImageCacheQueryDiskSync; if (options & SDWebImageQueryDiskSync) cacheOptions |= SDImageCacheQueryDiskSync;
operation.cacheOperation = [self.imageCache queryCacheOperationForKey:key options:cacheOptions done:^(UIImage *cachedImage, NSData *cachedData, SDImageCacheType cacheType) { operation.cacheOperation = [self.imageCache queryCacheOperationForKey:key options:cacheOptions done:^(UIImage *cachedImage, NSData *cachedData, SDImageCacheType cacheType) {
if (operation.isCancelled) { __strong __typeof(weakOperation) strongOperation = weakOperation;
[self safelyRemoveOperationFromRunning:operation]; if (!strongOperation || strongOperation.isCancelled) {
[self safelyRemoveOperationFromRunning:strongOperation];
return; return;
} }
@ -159,7 +162,7 @@
if (cachedImage && options & SDWebImageRefreshCached) { if (cachedImage && options & SDWebImageRefreshCached) {
// If image was found in the cache but SDWebImageRefreshCached is provided, notify about the cached image // If image was found in the cache but SDWebImageRefreshCached is provided, notify about the cached image
// AND try to re-download it in order to let a chance to NSURLCache to refresh it from server. // AND try to re-download it in order to let a chance to NSURLCache to refresh it from server.
[self callCompletionBlockForOperation:weakOperation completion:completedBlock image:cachedImage data:cachedData error:nil cacheType:cacheType finished:YES url:url]; [self callCompletionBlockForOperation:strongOperation completion:completedBlock image:cachedImage data:cachedData error:nil cacheType:cacheType finished:YES url:url];
} }
// download if no image or requested to refresh anyway, and download allowed by delegate // download if no image or requested to refresh anyway, and download allowed by delegate
@ -180,14 +183,16 @@
downloaderOptions |= SDWebImageDownloaderIgnoreCachedResponse; downloaderOptions |= SDWebImageDownloaderIgnoreCachedResponse;
} }
SDWebImageDownloadToken *subOperationToken = [self.imageDownloader downloadImageWithURL:url options:downloaderOptions progress:progressBlock completed:^(UIImage *downloadedImage, NSData *downloadedData, NSError *error, BOOL finished) { // `SDWebImageCombinedOperation` -> `SDWebImageDownloadToken` -> `downloadOperationCancelToken`, which is a `SDCallbacksDictionary` and retain the completed block bellow, so we need weak-strong again to avoid retain cycle
__strong __typeof(weakOperation) strongOperation = weakOperation; __weak typeof(strongOperation) weakSubOperation = strongOperation;
if (!strongOperation || strongOperation.isCancelled) { strongOperation.downloadToken = [self.imageDownloader downloadImageWithURL:url options:downloaderOptions progress:progressBlock completed:^(UIImage *downloadedImage, NSData *downloadedData, NSError *error, BOOL finished) {
__strong typeof(weakSubOperation) strongSubOperation = weakSubOperation;
if (!strongSubOperation || strongSubOperation.isCancelled) {
// Do nothing if the operation was cancelled // Do nothing if the operation was cancelled
// See #699 for more details // See #699 for more details
// if we would call the completedBlock, there could be a race condition between this block and another completedBlock for the same object, so if this one is called second, we will overwrite the new data // if we would call the completedBlock, there could be a race condition between this block and another completedBlock for the same object, so if this one is called second, we will overwrite the new data
} else if (error) { } else if (error) {
[self callCompletionBlockForOperation:strongOperation completion:completedBlock error:error url:url]; [self callCompletionBlockForOperation:strongSubOperation completion:completedBlock error:error url:url];
if ( error.code != NSURLErrorNotConnectedToInternet if ( error.code != NSURLErrorNotConnectedToInternet
&& error.code != NSURLErrorCancelled && error.code != NSURLErrorCancelled
@ -228,37 +233,27 @@
[self.imageCache storeImage:transformedImage imageData:(imageWasTransformed ? nil : downloadedData) forKey:key toDisk:cacheOnDisk completion:nil]; [self.imageCache storeImage:transformedImage imageData:(imageWasTransformed ? nil : downloadedData) forKey:key toDisk:cacheOnDisk completion:nil];
} }
[self callCompletionBlockForOperation:strongOperation completion:completedBlock image:transformedImage data:downloadedData error:nil cacheType:SDImageCacheTypeNone finished:finished url:url]; [self callCompletionBlockForOperation:strongSubOperation completion:completedBlock image:transformedImage data:downloadedData error:nil cacheType:SDImageCacheTypeNone finished:finished url:url];
}); });
} else { } else {
if (downloadedImage && finished) { if (downloadedImage && finished) {
[self.imageCache storeImage:downloadedImage imageData:downloadedData forKey:key toDisk:cacheOnDisk completion:nil]; [self.imageCache storeImage:downloadedImage imageData:downloadedData forKey:key toDisk:cacheOnDisk completion:nil];
} }
[self callCompletionBlockForOperation:strongOperation completion:completedBlock image:downloadedImage data:downloadedData error:nil cacheType:SDImageCacheTypeNone finished:finished url:url]; [self callCompletionBlockForOperation:strongSubOperation completion:completedBlock image:downloadedImage data:downloadedData error:nil cacheType:SDImageCacheTypeNone finished:finished url:url];
} }
} }
if (finished) { if (finished) {
[self safelyRemoveOperationFromRunning:strongOperation]; [self safelyRemoveOperationFromRunning:strongSubOperation];
} }
}]; }];
@synchronized(operation) {
// Need same lock to ensure cancelBlock called because cancel method can be called in different queue
operation.cancelBlock = ^{
[self.imageDownloader cancel:subOperationToken];
__strong __typeof(weakOperation) strongOperation = weakOperation;
[self safelyRemoveOperationFromRunning:strongOperation];
};
}
} else if (cachedImage) { } else if (cachedImage) {
__strong __typeof(weakOperation) strongOperation = weakOperation;
[self callCompletionBlockForOperation:strongOperation completion:completedBlock image:cachedImage data:cachedData error:nil cacheType:cacheType finished:YES url:url]; [self callCompletionBlockForOperation:strongOperation completion:completedBlock image:cachedImage data:cachedData error:nil cacheType:cacheType finished:YES url:url];
[self safelyRemoveOperationFromRunning:operation]; [self safelyRemoveOperationFromRunning:strongOperation];
} else { } else {
// Image not in cache and download disallowed by delegate // Image not in cache and download disallowed by delegate
__strong __typeof(weakOperation) strongOperation = weakOperation;
[self callCompletionBlockForOperation:strongOperation completion:completedBlock image:nil data:nil error:nil cacheType:SDImageCacheTypeNone finished:YES url:url]; [self callCompletionBlockForOperation:strongOperation completion:completedBlock image:nil data:nil error:nil cacheType:SDImageCacheTypeNone finished:YES url:url];
[self safelyRemoveOperationFromRunning:operation]; [self safelyRemoveOperationFromRunning:strongOperation];
} }
}]; }];
@ -323,18 +318,6 @@
@implementation SDWebImageCombinedOperation @implementation SDWebImageCombinedOperation
- (void)setCancelBlock:(nullable SDWebImageNoParamsBlock)cancelBlock {
// check if the operation is already cancelled, then we just call the cancelBlock
if (self.isCancelled) {
if (cancelBlock) {
cancelBlock();
}
_cancelBlock = nil; // don't forget to nil the cancelBlock, otherwise we will get crashes
} else {
_cancelBlock = [cancelBlock copy];
}
}
- (void)cancel { - (void)cancel {
@synchronized(self) { @synchronized(self) {
self.cancelled = YES; self.cancelled = YES;
@ -342,10 +325,10 @@
[self.cacheOperation cancel]; [self.cacheOperation cancel];
self.cacheOperation = nil; self.cacheOperation = nil;
} }
if (self.cancelBlock) { if (self.downloadToken) {
self.cancelBlock(); [self.manager.imageDownloader cancel:self.downloadToken];
self.cancelBlock = nil;
} }
[self.manager safelyRemoveOperationFromRunning:self];
} }
} }